The purpose of this research is to examine the impact of the changing sex composition of the medical profession on physicial specialty distribution. During the 1970's, the proportion of women in entering medical school classes increased from 9 to 25%, and preliminary analyses by the investigators have shown that this change resulted in a trend toward convergence in the male and female specialty distributions during graduate medical education (GME) and in certain other GME behaviors. The proposed project will elaborate this trend toward convergence using data on seven cohorts of U.S. medical school graduates (N equals 74,265) entering GME during 1970-1976. The project will: (1) determine whether certain control variables (individual and medical school characteristics) account for any portion of the convergence in first-year GME specialties; (2) examine the effects of the sex composition of medical school classes on subsequent specialty choices during GME; and (3) examine the effects of sex composition of the various specialities on specialty migration during GME and on final specialty selection during GME. The theoretical basis for this research derives from the sociological literature, in which Kanter has argued that the behavior of men and women in organizations is responsive to the proportional representation of the sexes. In this research, the sex composition of graduation cohorts, medical school classes, and specialty areas is treated as a "contextual variable" influencing the subsequent behavior of individuals.